The present invention relates to a recording disc cartridge including a magnetic recording disc or an optical recording disc enclosed in a disc case.
FIG. 1 shows a recording disc cartridge having a disc case 1 and a recording disc 2 rotatably enclosed in the disc case 1. In the recording disc cartridge of the above type, the disc case 1 is formed by a top case half 1a and a bottom case half 1b both of which are combined together by tapping screws or by an ultrasonic welding method. In the conventional recording disc cartridge, the top section 1a and the bottom section 1b are not shaped completely the same although they have almost similar shapes partly because they are fitted together by the engagement of projected walls formed on the peripheral part of one half of the disc case with recesses defined on the other half corresponding to the projected walls and partly because the detection notches on both of the halves are defined out of the center line of the disc case. Therefore, in the manufacturing process, two kinds of molds must be independently provided for each half and the top case and the bottom case half are independently molded and in turn each half thus formed must be assembled together one by one, thereby resulting in complicated work of assembling with expensive production cost in addition to a troublesome production control.